Just returned from Phuket.
Though the monsoon season, I had good and sunny days. The nights were wet though. I supposed I am lucky to have good sunny weather during my dives.
Racha Yai and Racha Noi are not too bad dive sites to go to, albeit the relatively high price even during monsoon. I joined my friends who were there for their open water certification. So I booked myself for 2 days of leisure diving. I managed to see quite a lot of interesting stuff there, not just corals and nemos. Had a good guide who helped me find a Sea Moth at Lucy's Reef. Many mantis shrimps, cleaner and anemone shrimps, tiny nudibranch, many aggro nesting titan triggers

, banded sea snake, flounders, garden eels. The visibility was quite good, probably 10-15m? And there wasn't much current. The eastern coasts of the 2 Racha islands are sheltered from monsoon, so it is quite calm to dive there.
I spoke to someone who went to Shark Point, King Cruiser Wreck etc and apparently, the visibility was good and he spotted quite abit of stuff there.
But just like Tioman, there are many patches of bleached coral reefs all over the few dive sites I went to. Some showed signs of recovery, but most really looked depressing. I heard from the dive guide that the weather seemed to turned for the better, and hopefully La Nina is really taking over El Nino, lowering the sea temperature for the reefs to recover.